Hillary Clinton has branded WikiLeaks' Australian founder Julian Assange a "nihilistic opportunist" who worked with Russia to damage her chance of becoming US president.
The defeated Democrat candidate also took aim at Australian-American Rupert Murdoch's conservative news empire Fox and warned Republican billionaire Donald Trump is the most dangerous president in history.
Assange and WikiLeaks are under investigation by the US Justice Department over the publication of top secret documents and thousands of emails from Democratic National Committee officials that undermined Mrs Clinton's presidential campaign last year.
Mrs Clinton said the material was stolen as part of a concerted operation between Russia, WikiLeaks and people in the US, who she said wanted to "weaponise that information" by denigrating her campaign against Mr Trump.
"I think Assange has become a nihilistic opportunist who does the bidding of a dictator," Mrs Clinton told ABC TV's Four Corners.
"He's a tool of Russian intelligence.
"If he's such a martyr of free speech, why doesn't WikiLeaks ever publish anything coming out of Russia?"
US intelligence officials have blamed Russia for stealing the Democrats' emails and documents as part of a deliberate effort to wreck Mrs Clinton's chances of becoming president.
They claim that WikiLeaks acted with Russian intelligence in publishing the documents.
Mr Assange has denied the Russian government as the source.
Mrs Clinton said the decision to leak the documents was linked to Mr Putin's desire to destabilise democracy and undermine the US, as well as the relationship America has with it allies including Australia.
She also believed that Mr Assange's personal dislike of her was a factor.
"I had a lot of history with him because I was secretary of state when WikiLeaks published a lot of very sensitive information from our State Department and our Defence Department," Mrs Clinton said.
Mr Assange has spent five years seeking refuge inside the Ecuador embassy in London to avoid extradition to Sweden to answer sexual assault charges.
While the charges were recently dropped, Mr Assange has remained in the embassy amid fears he could be extradited to the US.
Mrs Clinton also criticised Fox News, often decried for supporting the Republican party, for its "bad influence on our politics".
"They're an advocacy outfit; they're not journalism anymore," she said.
President Trump's Twitter diplomacy makes him a danger to the entire world, including Australia, Mrs Clinton said.
"He is impulsive, he lacks self-control, he is totally consumed by how he is viewed and what people think of him," she said.
"I think the whole world should be concerned and I think western democracies need to learn lessons."
Mrs Clinton believes the president is "being played" as he tough-talks North Korean leader Kim Jong-Un.
With no strategy for dealing with the rogue state's nuclear program, Mrs Clinton says she just hopes Mr Trump's support staff will help prevent a pre-emptive nuclear strike.
Her new book, she said, was designed to sound alarm bells in Australia and Europe before they follow the US leadership trajectory.
